A National Olympic Committee (NOC) may enter a maximum of 2 qualified athletes in each individual event, only if both athletes have attained the Olympic Qualifying Time (OQT). One athlete per event can potentially enter if they meet the Olympic Selection Time (OST) or if the quota of 900 athletes has not been targeted. NOCs may also permit swimmers regardless of time (1 per gender) under a Universality place, as long as they have no swimmers reaching either the standard entry time.[1]

In the relay events, a maximum of 16 qualifying teams in each relay event must be permitted to accumulate a total of 96 relay teams; each NOC may enter only one team. The first twelve teams in each relay event at the 2015 World Championships will automatically compete for the relay events at the Olympics; while the remaining four per relay event must obtain their fastest entry times based on the FINA World Rankings of 31 May 2016 during the process.[1]

Following the end of the qualification period, FINA will assess the number of athletes having achieved the OQT, the number of relay-only swimmers, and the number of Universality places, before inviting athletes with OST to fulfill the total quota of 900. Additionally, OST places will be distributed by event according to the position of the FINA World Rankings during the qualifying deadline (3 July 2016).[1]

The qualifying time standards must be obtained in World Championships, Continental Championships, Continental Qualification Events, National Championships and Trials, or International Competitions approved by FINA in the period between 1 March 2015 to 3 July 2016.[1]

Those who have achieved the Olympic Qualifying Time (OQT) or the Olympic Selection Time (OST), or have been guaranteed a Universality place are listed below for each of the following individual events:[3]

^"Argentine Martin Carrizo Off Olympic Roster Due To Failed Doping Test". SwimSwam. 2 June 2016. Retrieved 3 June 2016. Argentine Olympic Committee President Gerhard Werthein announced that Argentine swimmer Martin Carrizo has been removed from his nation’s Olympic roster after having failed a doping test. Carrizo tested positively for banned substance erythropoietin (EPO) after The Maria Lenk Trophy event in Rio last April, the event which also served as the Olympic Games’ swimming test event.